1. Technical Field
The present invention is directed toward fishing reels and more particularly toward a thrust washer system for fishing reels.
2. Background Art
In one type of closed-faced spin cast fishing reel, a reel frame or deck plate has an axial bore for receiving a center shaft. Formed integral with the center shaft or splined thereon is a pinion gear having helical teeth. When the center shaft is disposed within the bore of the deck plate the pinion gear extends rearwardly from the deck plate. The reel further includes a face gear cooperatively interengaging the pinion gear. Attached to the drive gear is a drive shaft which in turn is attached to a crank handle. When the crank handle is rotated in a line retrieving direction the drive gear is rotated which in turn causes rotation of the pinion gear and the center shaft associated therewith. Because of the helical angle of the pinion gear teeth, the pinion gear is axially thrust forward against the deck plate when the pinion gear is caused to rotate in a line retrieving direction. In addition, the drive gear causes a radial loading on the center shaft when the drive gear rotates the center shaft.
Many reels seat a conventional ball bearing at the rearward portion of the deck plate to dissipate the frictional resistance to rotation of the center shaft caused by the forward thrust (or axial load) of the pinion gear and the radial load of the drive gear discussed above. However, such ball bearings are expensive, not readily available in small sizes required by fishing reels and hard to turn if grease used on the reel gears seeps into the ball area. Moreover, while these ball bearings are effective in alleviating radial frictional forces opposing rotation of the center shaft, they are not very effective in dissipating axial frictional forces caused by the forward thrust of the pinion gear, as for example when the center shaft is caused to turn in a line retrieving direction. In particular, conventional ball bearings do not hold up for long periods of time under the repeated forward thrust of the pinion gear.
As an alternative to conventional ball bearings, some reels used an angular contact bearing. Angular contact bearings are designed to stand up to the axial forward thrust of the pinion gear. However, angular contact bearings are more expensive than conventional ball bearings and are inferior to conventional ball bearings for facilitating rotation of the center shaft under radial loads.
Another device used in the art for facilitating rotation of the center shaft under axial and radial loads is an OILITE.TM. bushing inserted into the bore in the deck plate, the OILITE.TM. bushing having a center shaft receiving bore therein. As is readily appreciated by those skilled in the art, OILITE.TM. bushings are typically made of a porous brass or bronze alloy with a lubricant such as oil permeated into the pores of the bushing. When heat is generated such as by rotation of the center shaft within the busing, lubrication is released from the pores of the bushing. Use of an OILITE.TM. bushing to facilitate rotation of the center shaft in the deck plate is often preferred over conventional ball bearings and angular contact bearings because it is less expensive and often times more durable.
When a pinion gear having helical teeth is rotated in a line retrieving direction, thereby subjecting the OILITE.TM. bushing to a forward thrust, lubrication seeps from the pores of the rearward facing edge of the OILITE.TM. bushing to facilitate easy rotation of the pinion gear and associated center shaft. However, under heavy and sustained forward thrusts, such as when a large fish is being reeled in, excessive heat and friction can cause the surface of the OILITE.TM. bushing contacting pinion gear to be depleted of lubrication, thus increasing the coefficient of friction between the OILITE.TM. bushing and the pinion gear and causing binding between the OILITE.TM. bushing and the pinion gear. Besides making line retrieval more difficult, this binding increases the wear on the reel drive system, in particular, the wear between the pinion gear and drive gear.